Commit Graph

304 Commits

Author SHA1 Message Date
Ahmed Bougacha 5228603387 [GlobalISel] Drop workaround for Legalizer member/class sharing a name. NFC.
MachineLegalizer used to be the name of both the class and the member,
causing GCC errors. r276522 fixed that by renaming the member to just
'Legalizer'.  The 'class' workaround isn't necessary anymore; drop it.

llvm-svn: 289848
2016-12-15 18:45:30 +00:00
Diana Picus 895c6aa6fd [ARM] GlobalISel: Remove unused members. NFCI
This silences some warnings that I didn't see with my host compiler.

llvm-svn: 286981
2016-11-15 16:42:10 +00:00
Diana Picus 90f0a84943 [ARM] Make sure GlobalISel is only initialized once. NFCI
Move some code inside the proper 'if' block to make sure it is only run once,
when the subtarget is first created. Things can still break if we use different
ARM target machines or if we have functions with different 'target-cpu' or
'target-features', we should fix that too in the future.

llvm-svn: 286974
2016-11-15 15:38:15 +00:00
Diana Picus 22274934f4 [ARM] Add plumbing for GlobalISel
Add GlobalISel skeleton, up to the point where we can select a ret void.

llvm-svn: 286573
2016-11-11 08:27:37 +00:00
Matthias Braun 8b38ffaa98 CodeGen/Passes: Pass MachineFunction as functor arg; NFC
Passing a MachineFunction as argument is more natural and avoids an
unnecessary round-trip through the logic determining the correct
Subtarget because MachineFunction already has a reference anyway.

llvm-svn: 285039
2016-10-24 23:23:02 +00:00
Mehdi Amini f42454b94b Move the global variables representing each Target behind accessor function
This avoids "static initialization order fiasco"

Differential Revision: https://reviews.llvm.org/D25412

llvm-svn: 283702
2016-10-09 23:00:34 +00:00
Zijiao Ma 53d55f45a1 Some places that could using TargetParser in LLVM. NFC.
llvm-svn: 278888
2016-08-17 02:08:28 +00:00
Oliver Stannard 8331aaee8f [ARM] Add support for embedded position-independent code
This patch adds support for some new relocation models to the ARM
backend:

* Read-only position independence (ROPI): Code and read-only data is accessed
  PC-relative. The offsets between all code and RO data sections are known at
  static link time. This does not affect read-write data.
* Read-write position independence (RWPI): Read-write data is accessed relative
  to the static base register (r9). The offsets between all writeable data
  sections are known at static link time. This does not affect read-only data.

These two modes are independent (they specify how different objects
should be addressed), so they can be used individually or together. They
are otherwise the same as the "static" relocation model, and are not
compatible with SysV-style PIC using a global offset table.

These modes are normally used by bare-metal systems or systems with
small real-time operating systems. They are designed to avoid the need
for a dynamic linker, the only initialisation required is setting r9 to
an appropriate value for RWPI code.

I have only added support to SelectionDAG, not FastISel, because
FastISel is currently disabled for bare-metal targets where these modes
would be used.

Differential Revision: https://reviews.llvm.org/D23195

llvm-svn: 278015
2016-08-08 15:28:31 +00:00
Matthias Braun 8f456fb18f ARM: Initialize LoadStore passes in TargetMachine
Initializing them in LLVMInitializeARMTarget() makes them visible early
enough for "llc -run-pass usage".

This required the pass to be renamed from "arm-load-store-opt" to
"arm-ldst-opt", because there already exists an arm-load-store-opt
cl::opt switch which would now clash with the passname getting added as
a switch in opt. On the bright side the pass name now matches the
DEBUG_TYPE name. Renamed "arm-prera-load-store-opt" to
"arm-repra-ldst-opt" as well for consistency.

llvm-svn: 275661
2016-07-16 02:24:10 +00:00
Rafael Espindola a895a0cd01 Add support for musl-libc on ARM Linux.
Patch by Lei Zhang!

llvm-svn: 273726
2016-06-24 21:14:33 +00:00
Rafael Espindola fe796dca90 Fix default reloc model on ARM.
llvm-svn: 271111
2016-05-28 10:41:15 +00:00
Renato Golin 9be88629d5 Revert "Revert "Map DynamicNoPIC to Static on non-darwin.""
This reverts commit r271096, as reverting it broke even more buildbots!

But that also means I'll break on ARM again... :(

llvm-svn: 271099
2016-05-28 04:47:13 +00:00
Renato Golin 4f22c51b09 Revert "Map DynamicNoPIC to Static on non-darwin."
This reverts commit r271052, as it broke some ARM buildbots.

llvm-svn: 271096
2016-05-28 04:24:26 +00:00
Rafael Espindola f9bda6805b Map DynamicNoPIC to Static on non-darwin.
DynamicNoPIC was only every used on darwin. This maps it to static on
ELF. It matches what is done on X86.

llvm-svn: 271052
2016-05-27 21:44:18 +00:00
Rafael Espindola 8c34dd8257 Delete Reloc::Default.
Having an enum member named Default is quite confusing: Is it distinct
from the others?

This patch removes that member and instead uses Optional<Reloc> in
places where we have a user input that still hasn't been maped to the
default value, which is now clear has no be one of the remaining 3
options.

llvm-svn: 269988
2016-05-18 22:04:49 +00:00
Rafael Espindola 38af4d6347 Trivial cleanups.
This just clang formats and cleans comments in an area I am about to
post a patch for review.

llvm-svn: 269946
2016-05-18 16:00:24 +00:00
Matthias Braun 31d19d43c7 CodeGen: Move TargetPassConfig from Passes.h to an own header; NFC
Many files include Passes.h but only a fraction needs to know about the
TargetPassConfig class. Move it into an own header. Also rename
Passes.cpp to TargetPassConfig.cpp while we are at it.

llvm-svn: 269011
2016-05-10 03:21:59 +00:00
Nirav Dave 8dd66e5753 Remove HasFnAttribute guards to getFnAttribute calls
These checks are redundant and can be removed

Reviewers: hans

Subscribers: llvm-commits, mzolotukhin

Differential Revision: http://reviews.llvm.org/D18564

llvm-svn: 264872
2016-03-30 15:41:12 +00:00
Tim Northover 042a6c1fe1 ARMv7k: base ABI decision on v7k Arch rather than watchos OS.
Various bits we want to use the new ABI actually compile with "-arch armv7k
-miphoneos-version-min=9.0". Not ideal, but also not ridiculous given how
slices work.

llvm-svn: 258975
2016-01-27 19:32:29 +00:00
Renato Golin 6d435f12f0 [EABI] Add LLVM support for -meabi flag
"GCC requires the freestanding environment provide memcpy, memmove, memset
and memcmp": https://gcc.gnu.org/onlinedocs/gcc-5.2.0/gcc/Standards.html

Hence in GNUEABI targets LLVM should not convert 'memops' to their equivalent
'__aeabi_memops'. This convertion violates GCC contract.

The -meabi flag controls whether or not LLVM will modify 'memops' in GNUEABI
targets.

Without -meabi: use the triple default EABI.
With -meabi=default: use the triple default EABI.
With -meabi=gnu: use 'memops'.
With -meabi=4 or -meabi=5: use '__aeabi_memops'.
With -meabi set to an unknown value: same as -meabi=default.

Patch by Vinicius Tinti.

llvm-svn: 252462
2015-11-09 12:40:30 +00:00
Tim Northover e0ccdc6de9 ARM: add backend support for the ABI used in WatchOS
At the LLVM level this ABI is essentially a minimal modification of AAPCS to
support 16-byte alignment for vector types and the stack.

llvm-svn: 251570
2015-10-28 22:46:43 +00:00
Peter Collingbourne 97aae40880 ARM/ELF: Better codegen for global variable addresses.
In PIC mode we were previously computing global variable addresses (or GOT
entry addresses) by adding the PC, the PC-relative GOT displacement and
the GOT-relative symbol/GOT entry displacement. Because the latter two
displacements are fixed, we ended up performing one more addition than
necessary.

This change causes us to compute addresses using a single PC-relative
displacement, resulting in a shorter code sequence. This reduces code size
by about 4% in a recent build of Chromium for Android.

As a result of this change we no longer need to compute the GOT base address
in the ARM backend, which allows us to remove the Global Base Reg pass and
SDAG lowering for the GOT.

We also now no longer use the GOT when addressing a symbol which is known
to be defined in the same linkage unit. Specifically, the symbol must have
either hidden visibility or a strong definition in the current module in
order to not use the the GOT.

This is a change from the previous behaviour where we would use the GOT to
address externally visible symbols defined in the same module. I think the
only cases where this could matter are cases involving symbol interposition,
but we don't really support that well anyway.

Differential Revision: http://reviews.llvm.org/D13650

llvm-svn: 251322
2015-10-26 18:23:16 +00:00
NAKAMURA Takumi 0a7d0ad95f Untabify.
llvm-svn: 248264
2015-09-22 11:15:07 +00:00
NAKAMURA Takumi 70ad98aca4 Reformat.
llvm-svn: 248261
2015-09-22 11:13:55 +00:00
Eric Christopher a4e5d3cf8e constify the Function parameter to the TTI creation callback and
propagate to all callers/users/etc.

llvm-svn: 247864
2015-09-16 23:38:13 +00:00
John Brawn f3324cf1a5 [ARM] Make GlobalMerge merge extern globals by default
Enabling merging of extern globals appears to be generally either beneficial or
harmless. On some benchmarks suites (on Cortex-M4F, Cortex-A9, and Cortex-A57)
it gives improvements in the 1-5% range, but in the rest the overall effect is
zero.

Differential Revision: http://reviews.llvm.org/D10966

llvm-svn: 243874
2015-08-03 12:13:33 +00:00
Daniel Sanders fbdab437f0 Where Triple has a suitable predicate, use it rather than the enum values. NFC.
Reviewers: mcrosier

Subscribers: llvm-commits, rengolin

Differential Revision: http://reviews.llvm.org/D10960

llvm-svn: 241469
2015-07-06 16:33:18 +00:00
Hao Liu 2cd34bb585 [ARM] Lower interleaved memory accesses to vldN/vstN intrinsics.
This patch also adds a function to calculate the cost of interleaved memory accesses.

E.g. Lower an interleaved load:
        %wide.vec = load <8 x i32>, <8 x i32>* %ptr, align 4
        %v0 = shuffle %wide.vec, undef, <0, 2, 4, 6>
        %v1 = shuffle %wide.vec, undef, <1, 3, 5, 7>
     into:
        %vld2 = { <4 x i32>, <4 x i32> } call llvm.arm.neon.vld2(%ptr, 4)
        %vec0 = extractelement { <4 x i32>, <4 x i32> } %vld2, i32 0
        %vec1 = extractelement { <4 x i32>, <4 x i32> } %vld2, i32 1

E.g. Lower an interleaved store:
        %i.vec = shuffle <8 x i32> %v0, <8 x i32> %v1, <0, 4, 8, 1, 5, 9, 2, 6, 10, 3, 7, 11>
        store <12 x i32> %i.vec, <12 x i32>* %ptr, align 4
     into:
        %sub.v0 = shuffle <8 x i32> %v0, <8 x i32> v1, <0, 1, 2, 3>
        %sub.v1 = shuffle <8 x i32> %v0, <8 x i32> v1, <4, 5, 6, 7>
        %sub.v2 = shuffle <8 x i32> %v0, <8 x i32> v1, <8, 9, 10, 11>
        call void llvm.arm.neon.vst3(%ptr, %sub.v0, %sub.v1, %sub.v2, 4)

Differential Revision: http://reviews.llvm.org/D10533

llvm-svn: 240755
2015-06-26 02:45:36 +00:00
Daniel Sanders c81f450f1a Clean up redundant copies of Triple objects. NFC
Summary:

Reviewers: rengolin

Reviewed By: rengolin

Subscribers: llvm-commits, rengolin, jholewinski

Differential Revision: http://reviews.llvm.org/D10382

llvm-svn: 239823
2015-06-16 15:44:21 +00:00
Daniel Sanders 3e5de88dac Replace string GNU Triples with llvm::Triple in TargetMachine. NFC.
Summary:
For the moment, TargetMachine::getTargetTriple() still returns a StringRef.

This continues the patch series to eliminate StringRef forms of GNU triples
from the internals of LLVM that began in r239036.

Reviewers: rengolin

Reviewed By: rengolin

Subscribers: ted, llvm-commits, rengolin, jholewinski

Differential Revision: http://reviews.llvm.org/D10362

llvm-svn: 239554
2015-06-11 19:41:26 +00:00
Daniel Sanders ed64d62c70 Replace string GNU Triples with llvm::Triple in computeDataLayout(). NFC.
Summary:
This continues the patch series to eliminate StringRef forms of GNU triples
from the internals of LLVM that began in r239036.

Reviewers: rengolin

Reviewed By: rengolin

Subscribers: llvm-commits, jfb, rengolin

Differential Revision: http://reviews.llvm.org/D10361

llvm-svn: 239538
2015-06-11 15:34:59 +00:00
Daniel Sanders a73f1fdb19 Replace string GNU Triples with llvm::Triple in MCSubtargetInfo and create*MCSubtargetInfo(). NFC.
Summary:
This continues the patch series to eliminate StringRef forms of GNU triples
from the internals of LLVM that began in r239036.

Reviewers: rafael

Reviewed By: rafael

Subscribers: rafael, ted, jfb, llvm-commits, rengolin, jholewinski

Differential Revision: http://reviews.llvm.org/D10311

llvm-svn: 239467
2015-06-10 12:11:26 +00:00
Akira Hatanaka 4a61619ff5 [ARM] Pass a callback to FunctionPass constructors to enable skipping execution
on a per-function basis.

Previously some of the passes were conditionally added to ARM's pass pipeline
based on the target machine's subtarget. This patch makes changes to add those
passes unconditionally and execute them conditonally based on the predicate
functor passed to the pass constructors. This enables running different sets of
passes for different functions in the module.

rdar://problem/20542263

Differential Revision: http://reviews.llvm.org/D8717

llvm-svn: 239325
2015-06-08 18:50:43 +00:00
Ahmed Bougacha 8207641251 [GlobalMerge] Take into account minsize on Global users' parents.
Now that we can look at users, we can trivially do this: when we would
have otherwise disabled GlobalMerge (currently -O<3), we can just run
it for minsize functions, as it's usually a codesize win.

Differential Revision: http://reviews.llvm.org/D10054

llvm-svn: 239087
2015-06-04 20:39:23 +00:00
Davide Italiano 141b2891cb [Target/ARM] Only enable OptimizeBarrierPass at -O1 and above.
Ideally this is going to be and LLVM IR pass (shared, among others
with AArch64), but for the time being just enable it if consumers
ask us for optimization and not unconditionally.

Discussed with Tim Northover on IRC.

llvm-svn: 237837
2015-05-20 21:40:38 +00:00
Eric Christopher 824f42f209 Migrate existing backends that care about software floating point
to use the information in the module rather than TargetOptions.

We've had and clang has used the use-soft-float attribute for some
time now so have the backends set a subtarget feature based on
a particular function now that subtargets are created based on
functions and function attributes.

For the one middle end soft float check go ahead and create
an overloadable TargetLowering::useSoftFloat function that
just checks the TargetSubtargetInfo in all cases.

Also remove the command line option that hard codes whether or
not soft-float is set by using the attribute for all of the
target specific test cases - for the generic just go ahead and
add the attribute in the one case that showed up.

llvm-svn: 237079
2015-05-12 01:26:05 +00:00
Ahmed Bougacha b96444efd1 [CodeGen] Split -enable-global-merge into ARM and AArch64 options.
Currently, there's a single flag, checked by the pass itself.
It can't force-enable the pass (and is on by default), because it
might not even have been created, as that's the targets decision.
Instead, have separate explicit flags, so that the decision is
consistently made in the target.

Keep the flag as a last-resort "force-disable GlobalMerge" for now,
for backwards compatibility.

llvm-svn: 234666
2015-04-11 00:06:36 +00:00
Renato Golin 4c8713969c Adds an option to disable ARM ld/st optim pass
Enabled by default, but it's useful when debugging with llc.

Patch by Ranjeet Singh.

llvm-svn: 233303
2015-03-26 18:38:04 +00:00
Ahmed Bougacha d1655cb1c0 [AArch64, ARM] Enable GlobalMerge with -O3 rather than -O1.
The pass used to be enabled by default with CodeGenOpt::Less (-O1).
This is too aggressive, considering the pass indiscriminately merges
all globals together.

Currently, performance doesn't always improve, and, on code that uses
few globals (e.g., the odd file- or function- static), more often than
not is degraded by the optimization.  Lengthy discussion can be found
on llvmdev (AArch64-focused;  ARM has similar problems):
  http://lists.cs.uiuc.edu/pipermail/llvmdev/2015-February/082800.html
Also, it makes tooling and debuggers less useful when dealing with
globals and data sections.

GlobalMerge needs to better identify those cases that benefit, and this
will be done separately.  In the meantime, move the pass to run with
-O3 rather than -O1, on both ARM and AArch64.

llvm-svn: 233024
2015-03-23 21:17:36 +00:00
Mehdi Amini 93e1ea167e Move the DataLayout to the generic TargetMachine, making it mandatory.
Summary:
I don't know why every singled backend had to redeclare its own DataLayout.
There was a virtual getDataLayout() on the common base TargetMachine, the
default implementation returned nullptr. It was not clear from this that
we could assume at call site that a DataLayout will be available with
each Target.

Now getDataLayout() is no longer virtual and return a pointer to the
DataLayout member of the common base TargetMachine. I plan to turn it into
a reference in a future patch.

The only backend that didn't have a DataLayout previsouly was the CPPBackend.
It now initializes the default DataLayout. This commit is NFC for all the
other backends.

Test Plan: clang+llvm ninja check-all

Reviewers: echristo

Subscribers: jfb, jholewinski, llvm-commits

Differential Revision: http://reviews.llvm.org/D8243

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 231987
2015-03-12 00:07:24 +00:00
Eric Christopher 7e70aba1a8 Recommit r231324 with a fix to the ARM execution domain code
to disable lane switching if we don't actually have the instruction
set we want to switch to. Models the earlier check above the
conditional for the pass.

The testcase is one that triggered with the assert that's added
as part of the fix, use it to avoid adding a new testcase as it
highlights the same problem.

llvm-svn: 231539
2015-03-07 00:12:22 +00:00
Hans Wennborg 6d8e6d5ee4 Revert r231324 "Remove the conditional addition of the execution dependency fixing"
See PR22799.

llvm-svn: 231348
2015-03-05 03:24:49 +00:00
Eric Christopher 385f4b36d8 Remove the conditional addition of the execution dependency fixing
pass from the ARM backend as the pass itself will detect any use
of the appropriate register class.

llvm-svn: 231324
2015-03-05 00:28:55 +00:00
Eric Christopher 63b44882ef Cleanup and remove a chunk of getARMSubtarget calls in the
ARM TargetMachine pass pipeline construction by pushing them down
into the appropriate pass.

llvm-svn: 231323
2015-03-05 00:23:40 +00:00
Eric Christopher ed47b22951 Rewrite the global merge pass to be subprogram agnostic for now.
It was previously using the subtarget to get values for the global
offset without actually checking each function as it was generating
code. Go ahead and solidify the current behavior and make the
existing FIXMEs more prominent.

As a note the ARM backend previously had a thumb1 and non-thumb1
set of defaults. Only the former was tested so I've changed the
behavior to only use that for now.

llvm-svn: 230245
2015-02-23 19:28:45 +00:00
Duncan P. N. Exon Smith 2cff9e19a2 ARM: Canonicalize access to function attributes, NFC
Canonicalize access to function attributes to use the simpler API.

getAttributes().getAttribute(AttributeSet::FunctionIndex, Kind)
  => getFnAttribute(Kind)

getAttributes().hasAttribute(AttributeSet::FunctionIndex, Kind)
  => hasFnAttribute(Kind)

llvm-svn: 229220
2015-02-14 02:24:44 +00:00
Chandler Carruth 30d69c2e36 [PM] Remove the old 'PassManager.h' header file at the top level of
LLVM's include tree and the use of using declarations to hide the
'legacy' namespace for the old pass manager.

This undoes the primary modules-hostile change I made to keep
out-of-tree targets building. I sent an email inquiring about whether
this would be reasonable to do at this phase and people seemed fine with
it, so making it a reality. This should allow us to start bootstrapping
with modules to a certain extent along with making it easier to mix and
match headers in general.

The updates to any code for users of LLVM are very mechanical. Switch
from including "llvm/PassManager.h" to "llvm/IR/LegacyPassManager.h".
Qualify the types which now produce compile errors with "legacy::". The
most common ones are "PassManager", "PassManagerBase", and
"FunctionPassManager".

llvm-svn: 229094
2015-02-13 10:01:29 +00:00
Chandler Carruth 8b04c0d26a [multiversion] Switch all of the targets over to use the
TargetIRAnalysis access path directly rather than implementing getTTI.

This even removes getTTI from the interface. It's more efficient for
each target to just register a precise callback that creates their
specific TTI.

As part of this, all of the targets which are building their subtargets
individually per-function now build their TTI instance with the function
and thus look up the correct subtarget and cache it. NVPTX, R600, and
XCore currently don't leverage this functionality, but its trivial for
them to add it now.

llvm-svn: 227735
2015-02-01 13:20:00 +00:00
Chandler Carruth 93dcdc47db [PM] Switch the TargetMachine interface from accepting a pass manager
base which it adds a single analysis pass to, to instead return the type
erased TargetTransformInfo object constructed for that TargetMachine.

This removes all of the pass variants for TTI. There is now a single TTI
*pass* in the Analysis layer. All of the Analysis <-> Target
communication is through the TTI's type erased interface itself. While
the diff is large here, it is nothing more that code motion to make
types available in a header file for use in a different source file
within each target.

I've tried to keep all the doxygen comments and file boilerplate in line
with this move, but let me know if I missed anything.

With this in place, the next step to making TTI work with the new pass
manager is to introduce a really simple new-style analysis that produces
a TTI object via a callback into this routine on the target machine.
Once we have that, we'll have the building blocks necessary to accept
a function argument as well.

llvm-svn: 227685
2015-01-31 11:17:59 +00:00
Chandler Carruth 705b185f90 [PM] Change the core design of the TTI analysis to use a polymorphic
type erased interface and a single analysis pass rather than an
extremely complex analysis group.

The end result is that the TTI analysis can contain a type erased
implementation that supports the polymorphic TTI interface. We can build
one from a target-specific implementation or from a dummy one in the IR.

I've also factored all of the code into "mix-in"-able base classes,
including CRTP base classes to facilitate calling back up to the most
specialized form when delegating horizontally across the surface. These
aren't as clean as I would like and I'm planning to work on cleaning
some of this up, but I wanted to start by putting into the right form.

There are a number of reasons for this change, and this particular
design. The first and foremost reason is that an analysis group is
complete overkill, and the chaining delegation strategy was so opaque,
confusing, and high overhead that TTI was suffering greatly for it.
Several of the TTI functions had failed to be implemented in all places
because of the chaining-based delegation making there be no checking of
this. A few other functions were implemented with incorrect delegation.
The message to me was very clear working on this -- the delegation and
analysis group structure was too confusing to be useful here.

The other reason of course is that this is *much* more natural fit for
the new pass manager. This will lay the ground work for a type-erased
per-function info object that can look up the correct subtarget and even
cache it.

Yet another benefit is that this will significantly simplify the
interaction of the pass managers and the TargetMachine. See the future
work below.

The downside of this change is that it is very, very verbose. I'm going
to work to improve that, but it is somewhat an implementation necessity
in C++ to do type erasure. =/ I discussed this design really extensively
with Eric and Hal prior to going down this path, and afterward showed
them the result. No one was really thrilled with it, but there doesn't
seem to be a substantially better alternative. Using a base class and
virtual method dispatch would make the code much shorter, but as
discussed in the update to the programmer's manual and elsewhere,
a polymorphic interface feels like the more principled approach even if
this is perhaps the least compelling example of it. ;]

Ultimately, there is still a lot more to be done here, but this was the
huge chunk that I couldn't really split things out of because this was
the interface change to TTI. I've tried to minimize all the other parts
of this. The follow up work should include at least:

1) Improving the TargetMachine interface by having it directly return
   a TTI object. Because we have a non-pass object with value semantics
   and an internal type erasure mechanism, we can narrow the interface
   of the TargetMachine to *just* do what we need: build and return
   a TTI object that we can then insert into the pass pipeline.
2) Make the TTI object be fully specialized for a particular function.
   This will include splitting off a minimal form of it which is
   sufficient for the inliner and the old pass manager.
3) Add a new pass manager analysis which produces TTI objects from the
   target machine for each function. This may actually be done as part
   of #2 in order to use the new analysis to implement #2.
4) Work on narrowing the API between TTI and the targets so that it is
   easier to understand and less verbose to type erase.
5) Work on narrowing the API between TTI and its clients so that it is
   easier to understand and less verbose to forward.
6) Try to improve the CRTP-based delegation. I feel like this code is
   just a bit messy and exacerbating the complexity of implementing
   the TTI in each target.

Many thanks to Eric and Hal for their help here. I ended up blocked on
this somewhat more abruptly than I expected, and so I appreciate getting
it sorted out very quickly.

Differential Revision: http://reviews.llvm.org/D7293

llvm-svn: 227669
2015-01-31 03:43:40 +00:00